Recently, there has been suggested a device that detects a decrease and the like in the concentration level of a driver who drives a vehicle and that informs the driver of the decrease in the concentration level. For example, in Patent Literature 1, there is disclosed a device that predicts the future occurrence of sleepiness, fatigue, and the like of a driver until the driver reaches a predetermined position on the basis of biometric information such as heart rate, respiratory rate, blink speed, and the like of the driver of a vehicle and on the basis of load exerted on the driver by a road until the vehicle reaches the predetermined position. The device of Patent Literature 1 calls to the attention of the driver in advance on the basis of the sleepiness of the driver at the predetermined position.